A great place to start - will lead you to results quickly without distracting you with parts of PowerShell you don't need right now.

From ss64.com
A nice online companion to the built-in PowerShell help.

M odels encapsulate everything that your application knows.
O perations encapsulate everything that your application does.
V iews mediate between your application and the user.
E vents are used to join all these components together safely.

There are problems with ranking things based only on their total upvote count or only the ratio or positive to total votes. The best solution uses something called a Wilson Confidence Interval and the formula is in here.

A thorough and very readable introduction to Javascript.